Ring decoy launching mechanism



22, 1963 w. F. LOEPER ETAL 3,107,617

RING DECOY LAUNCHING MECHANISM Filed April 11, 1962 INVENTORS WILLIAM F. LOEPER BYDONALDI w. MATTHEWS qaQ mqiw ATTORNEY? rates The invention described herein may be manufactured and used by or for the Government for governmental purposes without the payment to us of any royalty thereon.

This invention relates to a means for supporting and guiding decoy ring projectiles when launched in opposite directions from a missile. An object is to provide lightweight supporting and guiding means for such a decoy projectile when its periphery is oppositely tapered, when the weight of such supporting and guiding means must be but a fraction of the weight of the decoy projectile and when the permissible space longitudinally of the launching cylinders is extremely limited.

The shape of the projectile has required any supporting and guiding means to be unique in both function and construction. The requirements for such guiding means had to be so cramped for space and light in weight as to have complicated any solution.

According to this invention pressure build up in the opposite launching cylinders has been attained to get high velocity of the ejected projectiles in a short travel by use of a frangible connection. A piston and tube of smaller diameter than each projectile is used to economize space, conserve efiiciency, and avoid a need for bulky guide means for the ring projectile. A piston in the launching cylinder moves a projectile holder forward after the initial pressure build up and rupture of said frangible connection. In order to gain added velocity for this ring projectile being ejected, as soon as rupture of the frangible connection occurs, a spring under pressure is released to give the projectile an added impulse above that supplied by said piston and launching cylinder.

FIG. 1 is a view partly in section showing usual opposed launching cylinders ready to tire the decoy projectiles in opposite directions with [the housings.

FIG. 2 is a longitudinal section through only one of the guide cylinders which slide within a launching cylinder for ejecting the decoy projectile.

As shown in FIG. 1 :a usual propellant chamber is placed between opposed launching cylinders 11 and '12 for ejecting decoy projectiles carried on the supporting and guiding body holders 13 and 14 one of which is shown more in detail in FIG. 2. Electric wires 15 enter a primer housing 16 for firing the primer which in turn ignites the propellant in chamber 10 creating pressure for moving heads or pistons 18 and 19 after rupture of a frangible coupling 17. Within the launching cylinders 11 and 12 are the pistons 18 and 19 adapted to be moved outward under propellant pressure. Connected to these pistons 18 and 19 are the tubular supporting guides 20 and 21 slidably fitting within the cylinders 11 and 12 for supporting and guiding outward movement of the bodies 13 and 14 in which are received the holders for the decoy projectiles as is shown in FIG. 2.

In this FIG. 2 the body 22 is shown as threaded within the supporting tube 21) and enclosing the ring type decoy projectile 23 all around it and on one side. Within the body 22 is an auxiliary holder and guide 24 directly engaging the projectile 23. A helical spring 25 enclosed within housing 26 is compressed by a nut 27 on rod 28 and so held until rupture of coupling 17 had occurred. Prior to installation of the projectile in a missile having its cone represented by the inclined lines 8 and 9 in FIG. 1, a cover 29 is provided to assist in retaining the proatent ice jectile 23 in place in holder 24 and body 22. This cover may be held in place by one or more pins 35 frictionally or positively engaging a slightly recessed portion in the forward end portion of sides of holder 22. The holder 24 has a freely sliding fit within the inside of the side walls 33 of the cup shaped body 22. The resilient clamps 34 of which there are at least three, each of them includes a wedge shaped resilient pad 36 of foam rubber compressed between the tapered periphery of the projectile and a metal angle piece 34 having inwardly bent sides, one on the outer side 37 of the pad 36 and the other bent side 38 being shorter and received within a groove shown on the periphery of the holder 24. Before inserting the projectile 23 in place the cover 29 is removed by its handle 30. Screws 3 1 which had been inserted for joining holder 24- to body 22 are removed to allow separation of the projectile 23, holder 24 and body 22 after firing.

In operation on closing a primer circuit 15 and firing the primer in housing 16, the propellant in chamber 10 is ignited creating gas pressure acting on the pistons 18 and 19 within the launching cylinders 11 and 12 and moving those pistons in opposite directions after rupture of the frangible coupling 17. As the pistons move outwardly the supporting and guiding tubes 20 and 21 for the projectile-s move with their pistons and are guided by the outer launching cylinders 11 and 12. Referring to FIG. 2 the cover 29 has been removed and retaining screws 31 holding the body 22 and holder together have been removed, and the nut 27 has been tightened to compress spring 25. The clamps 36 have been previously inserted. After piston 18' and tube 20 start moving under propellant pressure, upon rupture of coupling 17, the spring 25 immediately expands pushing holder 24 and decoy projectile 23 ahead of the movement of holder 22 with perhaps an acceleration of about 5 feet per second faster than that of the body 22 and tube 20, depending on the strength of spring 25. As the tube 24 and body '22 are moved initially the holder 24 and projectile 23 likewise move outward during elongation of coupling 17 and before its fracture. After fracture the propellant pressure has built up to a value sufficient for moving the piston 18' and what it is connected to a more rapid rate while the body 22 is being moved outwardly under the built up propellant pressure the spring 25 is pressing against body 22 and moving the holder 24 and projectile 23 more rapidly outward. Movement of holder 24- at a faster rate than body 22 continues until pin 39 through rod 28 abuts the piston 18 and cutting short the additional impulse given the projectile over and above that due to body 22. By or before that cutting off of additional movement to holder 24- and projectile 23 has been reached the projectile will have been released from the holder 24 and body 22 and moved clear of the outer edge of the wall 33. When the decoy projectile has been moved that far the clamps 34 fly radially outward to be free of the compression in the rubber 36, moving the short side or flange 38 out of the groove in the holder 24 in which it is placed and in this same manner each of the 3 or more clamps are removed due largely to a release of pressure on them. The decoy projectile continues its flight ahead of the clamps, holder, and body, and this group of elements with tube 20, rod 28 and piston may continue its outward movement until free of the launcher cylinder when it will fall away from the missile.

Among the advantages of this invention may be mentioned the imparting of a suitable velocity to the decoy projectile 23 depending upon the degree of pressure build up before the rapid acceleration of the parts begins after rupture of the coupling 17. Thus initial build up of pressure depends on the combustion rate of the propellant and upon the size of the frangible coupling and its ultimate strength before rupture of such coupling. The velocity guided during ejection with little clearance 'space hetween and longitudinally of the launching cylinder and axial depth of the projectile and the side of the missile cone through which it is launched. This 16 /2 pound decoy projectile is thus enabled to be satisfactorily sped on its mission by means of the existing launching cylinders with less additional Weight for the supporting and guiding attachment that is the weight of the decoy projectile. The tube 20, and pants 22, 24 and28 are made of aluminum for lightness in weight. The thrust given the projectile in addition to that imparted by the piston 18 and tube 20 is axial of the tube and projectile. The piston and tube20'move only about A of an inch before rupture of coupling 17 occurs when sprping 25 begins imparting the additional thrust mentioned for the ring projectile 23. V

The total movement of the 'projectile'while gaining its desired velocity is only about 4 inches before its release. The existing launching cylinders have to support and guide the projectile during its ejection. As shown in FIG. 1 each body 22 abuts the launching cylinder 11 prior to firing the propellant. An ring packing 32 is provided in piston 18 to reduce leakage around rod 28. To assemble the pistons 18 and 19 with their guides 20 and 21 with frangible coupling 17, at least one of the bodies 22 must be unscrewed from its guide tube to allow the two guide tubes, pistons and rods to be inserted with coupling 17 between them from outside of one of the launching cylinders. Besides supporting and guiding a projectile, tube 29 functions as part of an applicator'to transfer .thrust from piston 18 to the body 22, and the holder 24 functions as a second load applicator. In the walls 8 and 9 of the cone opposite the holders 13 and 14 are removable doors forming no part of this invention but which are removable on or before firing the decoys in order that the launching of such decoys may not be impeded.

We claim: I

l. A combination comprising a launching cylinder, a piston therein, a propellant chamber, connected to said cylinder for actuating said piston on ignition of propellant, means for igniting said propellant, a load applicator connected to said piston for imparting a thrust to a load from said piston through said applicator, and means for imparting an additional thrust to a load, said last mentioned means comprising a second load applicator between a load and the first mentioned applicator, a rod extending through said piston for movement with initial movement of said piston and applicators under propellant pressure, a frangible coupling to said rod for resisting said initial movement of said piston and applicator under propellant pressure, and a spring between said first and second mentioned load applicator for imparting an additional thrust on the second load applicator after rupture of said frangible coupling, whereby said additional thrust may vary with the strength of said spring and be applied to a load during movement of said first mentioned applicator.

2. A combination according to claim 1 in which an abutment on the rod limits its movement under influence of said spring.

3. In a missile having a nose cone, opposed pressure cyinders for firing decoy projectiles out of said cone and launching cylinders in opposite directions and simultaneously when under substantially equal impulses and of substantially equal weights to avoid any recoil being unbalanced and in danger of throwing said missile off its intended course, the combination therewith of the im provement for supporting and guiding said decoy projectiles when of ring shape and each having substantially equal and oppositely tapered peripheral portions, said improvement including for each decoy projectile a supporting and guiding tube slidable in'each launching cylinder, a head closing the inner end portion of each such tube, a cup shaped body threaded to each tube outer end portion, a cup shaped holder slidable within each body portion, a helical spring axially within said body and holder, for cooperation with each, a rod axially through each of said tunes for holding its spring compressed, a frangible connection between said rods and within said launching cylinders, an abutment pin through each rod between said frangible connection and the head of each tube, an inner side wall of said holder being tapered to receive the taper on one half portion of the decoy projectile ring periphery, a plurality of substantially equally angularly spaced resilient clamps held to said holder and I compressed between a side portion of said body and an outer tapered portion of the projectile periphery, whereby on firing an explosive charge between said launching cylinders the pressure on each tube head moves the tubes outwardly until said connection ruptures, when each spring pushes each decoy projectile outwardly faster than the outward movement of said cup shaped body whi'ch supports and guides the outward movement of its decoy projectile and its holder until said abutment pin engages its tube head and limits outward movement of said holder for separation of said decoy projectile therefrom and the radial outward movement of said clamps upon release of their compression leaves the projectile itself free of any launching attachment parts.

4. An attachment fora launching cylinder in a missile cone whereby a decoy ring type projectile of much larger diameter than said cylinder may be supported and guided by said cylinder while being ejected thereby, said attachment comprising a supporting and guiding tube for said projectile slidable within said cylinder, a head or piston closing an inner end of said tube, a cup shaped body secured, to the outer end of said tube and facing outward, a cup shaped holder of less depth than said body and slidable within the body side walls for holding a ring type projectile, said holder being clamped to said body before beginning of an outward movement by said tube and body, a rod secured to said holder and extending through said tube and piston to a frangible coupling, a spring between said holder and body for imparting an additional impulse to said projectile and holder after rupture of said coupling, a resilient clamp for a tapered periphery of a projectile, and an abutment on said rod for engagement with said piston to limit outward movement of said holder under impulse of said spring. 

1. A COMBINATION COMPRISING A LAUNCHING CYLINDER, A PISTON THEREIN, A PROPELLANT CHAMBER, CONNECTED TO SAID CYLINDER FOR ACTUATING SAID PISTON ON IGNITION OF PROPELLANT, MEANS FOR IGNITING SAID PROPELLANT, A LOAD APPLICATOR CONNECTED TO SAID PISTON FOR IMPARTING A THRUST TO A LOAD FROM SAID PISTON THROUGH SAID APPLICATOR, AND MEANS FOR IMPARTING AN ADDITIONAL THRUST TO A LOAD, SAID LAST MENTIONED MEANS COMPRISING A SECOND LOAD APPLICATOR BETWEEN A LOAD AND THE FIRST MENTIONED APPLICATOR, A ROD EXTENDING THROUGH SAID PISTON FOR MOVEMENT WITH INITIAL MOVEMENT OF SAID PISTON AND APPLICATORS UNDER PROPELLANT PRESSURE, A FRANGIBLE COUPLING TO SAID ROD FOR RESISTING SAID INITIAL MOVEMENT OF SAID PISTON AND APPLICATOR UNDER PROPELLANT PRESSURE, AND A SPRING BETWEEN SAID FIRST AND SECOND MENTIONED LOAD APPLICATOR FOR IMPARTING AN ADDITIONAL THRUST ON THE SECOND LOAD APPLICATOR AFTER RUPTURE OF SAID FRANGIBLE COUPLING, WHEREBY SAID ADDITIONAL THRUST MAY VARY WITH THE STRENGTH OF SAID SPRING AND BE APPLIED TO A LOAD DURING MOVEMENT OF SAID FIRST MENTIONED APPLICATOR. 